My shared instance website is costing about £20 GBP per month, and this is detailed as 'Compute Hours' in my bill.

According to Scott Gu's blog
"You pay for a shared mode web-site using the standard “pay as you go” model that we support with other features of Windows Azure (meaning no up-front costs, and you pay only for the hours that the feature is enabled). A web-site running in shared mode costs only 1.3 cents/hr during the preview (so on average $9.36/month)."

The shared instance model provides support for custom domain names, 1
GB of storage, and unlimited outbound data transfer charged on the
terms of your Windows Azure subscription at the standard Pay-As-You-Go
rates. Up to three instances per Web site may be deployed at an
additional cost.

Under the shared instance model, you will receive the following
benefits:

The ability to assign your custom host or domain name Outbound traffic
charged at Pay-As-You-Go rates; unlimited inbound data transfer 1 GB
storage (shared by all sites) 20 MB of a third-party, MySQL database
Each Web site operated under the shared instance model will be charged
at $0.02 / hour (approx. $14.40 / month) per Web Site instance at
general availability. During preview, a 33% discount will be applied
for an effective monthly rate of $9.60 / month, per Web Site instance.
During preview, all paid shared instance hours will be billed using
the current Cloud Services small compute meter, except we will emit
1/9th of the Cloud Services small compute hours to deliver the
discounted pricing of $9.60 / month per Web Site instance. The monthly
calculation per paid shared Web Site instance is as follows: 720 hours
* 1/9 * $0.12 =$9.60."

So what I am misunderstanding? A shared website at the this moment in time (Jan 2013) should cost less than $10 per month.

I did, they said I had three instances running, but they couldn't tell me what site the instances were for. Confused myself massively now because I don't remember fiddling with the instance settings.
– Marvin RounceJan 19 '13 at 15:03